Flame-retardant epoxy resin composition and laminate made with the same

Abstract

A flame-retardant epoxy resin composition includes an epoxy resin, a curing agent, and a metal hydroxide, wherein the curing agent as a phenolic resin (C) containing, in the molecular chain, structural units derived from a phenol (A) and structural units derived from an aromatic compound (B) other than the phenol (A), or the epoxy resin is a novolac epoxy resin CD) obtained by subjecting the phenolic hydroxyl groups of the phenolic resin (C) to etherification with glycidyl. The composition has a high degree of flame retardancy.

What is claimed is:  
     
       1. A flame-retardant epoxy resin composition comprising an epoxy resin, a curing agent, a metal hydroxide, and a silicone compound of a branched structure main chain having an aromatic-derived group, 
       wherein the curing agent is a phenolic resin (C) containing, in a molecular chain, a structural unit derived from a phenol (A) and a structural unit derived from an aromatic compound (B) other than the phenol (A).  
     
     
       2. A flame-retardant epoxy resin composition according to  claim 1 , wherein the aromatic compound (B) is a compound selected from the group consisting of biphenyl and its derivatives, benzene and its derivatives, diphenyl ether and its derivatives, naphthalene and its derivatives, anthracene and its derivatives, fluorene and its derivatives, bisphenol fluorene and its derivatives, bisphenol S and its derivatives, bisphenol F and its derivatives and bisphenol A and its derivatives. 
     
     
       3. A flame-retardant epoxy resin composition according to  claim 1 , wherein the phenolic resin (C) has a recurring unit represented by either of the following formulas (I) to (IV):                    
       (wherein X 1  and X 2  are each independently a C 1-6  unsaturated chain structure linking group, or a C 1-6  substituted or unsubstituted alkylene group; and R 1  is a phenylene group, a biphenylene group or a group derived from these groups). 
     
     
       4. A flame-retardant epoxy resin composition according to  claim 1 , wherein a content of the metal hydroxide is 10% by mass to 70% by mass relative to a total amount of the flame-retardant epoxy resin composition. 
     
     
       5. A flame-retardant epoxy resin composition according to  claim 1 , wherein a content of the metal hydroxide is 5% by mass to 70% by mass relative to a total amount of the flame-retardant epoxy resin composition. 
     
     
       6. A flame-retardant epoxy resin composition according to  claim 1 , wherein the silicone compound contains a unit (T unit) represented by the formula RSiO 1.5 . 
     
     
       7. A flame-retardant epoxy resin composition according to  claim 1 , wherein the silicone compound contains a group reactive with the epoxy resin and/or the curing agent. 
     
     
       8. A flame-retardant epoxy resin composition according to  claim 7 , wherein the reactive group is hydroxyl group, C 1-5  alkoxy group, epoxy group or carboxyl group. 
     
     
       9. A flame-retardant epoxy resin composition according to  claim 1 , impregnated and cured into a substrate of a laminate. 
     
     
       10. A flame-retardant epoxy resin composition according to  claim 1 , wherein the metal hydroxide is a metal oxide containing at least one element selected from the group consisting of aluminum, magnesium, zinc, boron, calcium, nickel, cobalt, tin, molybdenum, copper, iron and titanium. 
     
     
       11. A flame-retardant epoxy resin composition according to  claim 10 , wherein the metal hydroxide is aluminum hydroxide, magnesium hydroxide or zinc borate. 
     
     
       12. An epoxy resin varnish solution obtained by dispersing the flame-retardant epoxy resin composition set forth in  claim 1 , in an organic solvent. 
     
     
       13. A prepreg obtained by impregnating the flame-retardant epoxy resin composition set forth in  claim 1 , into a substrate and curing the impregnated composition. 
     
     
       14. A flame-retardant epoxy resin composition comprising an epoxy resin, a curing agent, a metal hydroxide, and a silicone compound of a branched structure main chain having an aromatic-derived group, 
       wherein the epoxy resin is a novolac epoxy resin (D) obtained by glycidyletherifying a phenolic hydroxyl group of a phenolic resin (C) containing, in a molecular chain, a structural unit derived from a phenol (A) and a structural unit derived from an aromatic compound (B) other than the phenol (A).  
     
     
       15. A flame-retardant epoxy resin composition according to  claim 14 , wherein the aromatic compound (B) is a compound selected from the group consisting of biphenyl and its derivatives, benzene and its derivatives, diphenyl ether and its derivatives, naphthalene and its derivatives, anthracene and its derivatives, fluorene and its derivatives, bisphenol fluorene and its derivatives, bisphenol S and its derivatives, bisphenol F and its derivatives and bisphenol A and its derivatives. 
     
     
       16. A lame-retardant epoxy resin composition according to  claim 14 , wherein the phenolic resin (C) has a recurring unit represented by either of the following formulas (I) to (IV):                    
       (wherein X 1  and X 2  are each independently a C 1-6  unsaturated chain structure linking group, or a C 1-6  substituted or unsubstituted alkylene group; and R 1  is a phenylene group, a biphenylene group or a group derived from these groups). 
     
     
       17. A flame-retardant epoxy resin composition according to  claim 14 , wherein a content of the metal hydroxide is 10% by mass to 70% by mass relative to a total amount of the flame-retardant epoxy resin composition. 
     
     
       18. A flame-retardant epoxy resin composition according to  claim 14 , wherein a content of the metal hydroxide is 5% by mass to 70% by mass relative to a total amount of the flame-retardant epoxy resin composition. 
     
     
       19. A flame-retardant epoxy resin composition according to  claim 14 , wherein the silicone compound contains a unit (T unit) represented by the formula RSiO 1.5 . 
     
     
       20. A flame-retardant epoxy resin composition according to  claim 14 , wherein the silicone compound contains a group reactive with the epoxy resin and/or the curing agent. 
     
     
       21. A flame-retardant epoxy resin composition according to  claim 20 , wherein the reactive group is hydroxyl group, C 1-5  alkoxy group, epoxy group or carboxyl group. 
     
     
       22. A flame-retardant epoxy resin composition according to  claim 14 , impregnated and cured into a substrate of a laminate. 
     
     
       23. A flame-retardant epoxy resin composition according to  claim 14 , wherein the metal hydroxide is a metal oxide containing at least one element selected from the group consisting of aluminum, magnesium, zinc, boron, calcium, nickel, cobalt, tin, molybdenum, copper, iron and titanium. 
     
     
       24. A flame-retardant epoxy resin composition according to  claim 23 , wherein the metal hydroxide is aluminum hydroxide, magnesium hydroxide or zinc borate. 
     
     
       25. An epoxy resin varnish solution obtained by dispersing the flame-retardant epoxy resin composition set forth in  claim 14 , in an organic solvent. 
     
     
       26. A prepreg obtained by impregnating the flame-retardant epoxy resin composition set forth in  claim 14 , into a substrate and curing the impregnated composition. 
     
     
       27. A flame-retardant epoxy resin composition comprising an epoxy resin, a curing agent, a metal hydroxide, and a silicone compound of a branched structure main chain having an aromatic-derived group, 
       wherein the curing agent is a phenolic resin (C) containing, in a molecular chain, a structural unit derived from a phenol (A) and a structural unit derived from an aromatic compound (B) other than the phenol (A), and  
       the epoxy resin is a novolac epoxy resin (D) obtained by glycidyletherifying a phenolic hydroxyl group of a phenolic resin (C′) containing, in a molecular chain, a structural unit derived from a phenol (A′) and a structural unit derived from an aromatic compound (B′) other than the phenol (A′).  
     
     
       28. A flame-retardant epoxy resin composition according to  claim 27 , wherein the aromatic compound (B) is a compound selected from the group consisting of biphenyl and its derivatives, benzene and its derivatives, diphenyl ether and its derivatives, naphthalene and its derivatives, anthracene and its derivatives, fluorene and its derivatives, bisphenol fluorene and its derivatives, bisphenol S and its derivatives, bisphenol F and its derivatives and bisphenol A and its derivatives. 
     
     
       29. A flame-retardant epoxy resin composition according to  claim 27 , wherein the phenolic resin (C) has a recurring unit represented by either of the following formulas (I) to (IV):                    
       wherein X 1  and X 2  are each independently a C 1-6  unsaturated chain structure linking group, or a C 1-6  substituted or unsubstituted alkylene group; and R 1  is a phenylene group, a biphenylene group or a group derived from these groups). 
     
     
       30. A flame-retardant epoxy resin composition according to  claim 27 , wherein a content of the metal hydroxide is 10% by mass to 70% by mass relative to a total amount of the flame-retardant epoxy resin composition. 
     
     
       31. A flame-retardant epoxy resin composition according to  claim 27 , wherein a content of the metal hydroxide is 5% by mass to 70% by mass relative to a total amount of the flame-retardant epoxy resin composition. 
     
     
       32. A flame-retardant epoxy resin composition according to  claim 27 , wherein the silicone compound contains a unit (T unit) represented by the formula RSiO 1.5 . 
     
     
       33. A flame-retardant epoxy resin composition according to  claim 27 , wherein the silicone compound contains a group reactive with the epoxy resin and/or the curing agent. 
     
     
       34. A flame-retardant epoxy resin composition according to  claim 33 , wherein the reactive group is hydroxyl group, C 1-5  alkoxy group, epoxy group or carboxyl group. 
     
     
       35. A flame-retardant epoxy resin composition according to  claim 27 , impregnated and cured into a substrate of a laminate. 
     
     
       36. A flame-retardant epoxy resin composition according to  claim 27 , wherein the metal hydroxide is a metal hydroxide containing at least one element selected from the group consisting of aluminum, magnesium, zinc, boron, calcium, nickel, cobalt, tin, molybdenum, copper, iron and titanium. 
     
     
       37. A flame-retardant epoxy resin composition according to  claim 36 , wherein the metal hydroxide is aluminum hydroxide, magnesium hydroxide or zinc borate. 
     
     
       38. An epoxy resin varnish solution obtained by dispersing the flame-retardant epoxy resin composition set forth in  claim 27 , in an organic solvent. 
     
     
       39. A prepreg obtained by impregnating the flame-retardant epoxy resin composition set forth in  claim 27 , into a substrate and curing the impregnated composition. 
     
     
       40. A laminate obtained by impregnating a flame-retardant epoxy resin composition comprising an epoxy resin, a curing agent, a metal hydroxide, and a silicone compound of a branched structure main chain having an aromatic-derived group, into a substrate, curing the impregnated composition to obtain a prepreg, laminating a plurality of the prepregs, and hot-pressing them, 
       wherein the curing agent is a phenolic resin (C) containing, in a molecular chain, a structural unit derived from a phenol (A) and a structural unit derived from an aromatic compound (B) other than the phenol (A).  
     
     
       41. A laminate according to  claim 40 , wherein the aromatic compound (B) is a compound selected from the group consisting of biphenyl and its derivatives, benzene and its derivatives, diphenyl ether and its derivatives, naphthalene and its derivatives, anthracene and its derivatives, fluorene and its derivatives, bisphenol fluorene and its derivatives, bisphenol S and its derivatives, bisphenol F and its derivatives and bisphenol A and its derivatives. 
     
     
       42. A laminate according to  claim 40 , wherein the phenolic resin (C) has a recurring unit represented by either of the following formulas (I) to (IV):                    
       (wherein X 1  and X 2  are each independently a C 1-6  unsaturated chain structure linking group, or a C 1-6  substituted or unsubstituted alkylene group; and R 1  is a phenylene group, a biphenylene group or a group derived from these groups). 
     
     
       43. A laminate according to  claim 40 , wherein a content of the metal hydroxide is 5% by mass to 70% by mass relative to a total amount of the flame-retardant epoxy resin composition. 
     
     
       44. A laminate according to  claim 40 , wherein the silicone compound contains a unit (T unit) represented by the formula RSiO 1.5 . 
     
     
       45. A laminate according to  claim 40 , wherein the silicone compound contains a group reactive with the epoxy resin and/for the curing agent. 
     
     
       46. A laminate according to  claim 45 , wherein the reactive group is hydroxyl group, C 1-5  alkoxy group, epoxy group or carboxyl group. 
     
     
       47. A laminate according to  claim 40 , wherein the metal hydroxide is a metal oxide containing at least one element selected from the group consisting of aluminum, magnesium, zinc, boron, calcium, nickel, cobalt, tin, molybdenum, copper, iron and titanium. 
     
     
       48. A laminate according to  claim 40 , wherein the metal hydroxide is aluminum hydroxide, magnesium hydroxide or zinc borate. 
     
     
       49. A laminate obtained by impregnating a flame-retardant epoxy resin composition comprising an epoxy resin, a curing agent, a metal hydroxide, and a silicone compound of a branched structure main chain having an aromatic-derived group, into a substrate, curing the impregnated composition to obtain a prepreg, laminating a plurality of the prepregs, and hot-pressing them, 
       wherein the epoxy resin is a novolac epoxy resin (D) obtained by glycidyletherifying a phenolic hydroxyl group of a phenolic resin (C) containing, in a molecular chain, a structural unit derived from a phenol (A) and a structural unit derived from an aromatic compound (B) other than the phenol (A).  
     
     
       50. A laminate according to  claim 49 , wherein the aromatic compound (B) is a compound selected from the group consisting of biphenyl and its derivatives, benzene and its derivatives, diphenyl ether and its derivatives, naphthalene and its derivatives, anthracene and its derivatives, fluorene and its derivatives, bisphenol fluorene and its derivatives, bisphenol S and its derivatives, bisphenol F and its derivatives and bisphenol A and its derivatives. 
     
     
       51. A laminate according to  claim 49 , wherein the phenolic resin (C) has a recurring unit represented by either of the following formulas (I) to (IV):                    
       (wherein X 1  and X 2  are each independently a C 1-6  unsaturated chain structure linking group, or a C 1-6  substituted or unsubstituted alkylene group; and R 1  is a phenylene group, a biphenylene group or a group derived from these groups). 
     
     
       52. A laminate according to  claim 49 , wherein a content of the metal hydroxide is 5% by mass to 70% by mass relative to a total amount of the flame-retardant epoxy resin composition. 
     
     
       53. A laminate according to  claim 49 , wherein the silicone compound contains a unit (T unit) represented by the formula RSiO 1.5 . 
     
     
       54. A laminate according to  claim 49 , wherein the silicone compound contains a group reactive with the epoxy resin and/or the curing agent. 
     
     
       55. A laminate according to  claim 54 , wherein the reactive group is hydroxyl group, C 1-5  alkoxy group, epoxy group or carboxyl group. 
     
     
       56. A laminate according to  claim 49 , wherein the metal hydroxide is a metal oxide containing at least one element selected from the group consisting of aluminum, magnesium, zinc, boron, calcium, nickel, cobalt, tin, molybdenum, copper, iron and titanium. 
     
     
       57. A laminate according to  claim 49 , wherein the metal hydroxide is aluminum hydroxide, magnesium hydroxide or zinc borate. 
     
     
       58. A laminate obtained by impregnating a flame-retardant epoxy resin composition comprising an epoxy resin, a curing agent, a metal hydroxide, and a silicone compound of a branched structure main chain having an aromatic-derived group, into a substrate, curing the impregnated composition to obtain a prepreg, laminating a plurality of the prepregs, and hot-pressing them, 
       wherein the curing agent is a phenolic resin (C) containing, in a molecular chain, a structural unit derived from a phenol (A) and a structural unit derived from an aromatic compound (B) other than the phenol (A), and  
       the epoxy resin is a novolac epoxy resin (D) obtained by glycidyletherifying a phenolic hydroxyl group of a phenolic resin (C′) containing, in a molecular chain, a structural unit derived from a phenol (A′) and a structural unit derived from an aromatic compound (B′) other than the phenol (A′).  
     
     
       59. A laminate according to  claim 58 , wherein the aromatic compound (B) is a compound selected from the group consisting of biphenyl and its derivatives, benzene and its derivatives, diphenyl ether and its derivatives, naphthalene and its derivatives, anthracene and its derivatives, fluorene and its derivatives, bisphenol fluorene and its derivatives, bisphenol S and its derivatives, bisphenol F and its derivatives and bisphenol A and its derivatives. 
     
     
       60. A laminate according to  claim 58 , wherein the phenolic resin (C) has a recurring unit represented by either of the following formulas (I) to (IV):                    
       (wherein X 1  and X 2  are each independently a C 1-6  unsaturated chain structure linking group, or a C 1-6  substituted or unsubstituted alkylene group; and R 1  is a phenylene group, a biphenylene group or a group derived from these groups). 
     
     
       61. A laminate according to  claim 58 , wherein a content of the metal hydroxide is 5% by mass to 70% by mass relative to a total amount of the flame-retardant epoxy resin composition. 
     
     
       62. A laminate according to  claim 58 , wherein the silicone compound contains a unit (T unit) represented by the formula RSiO 1.5 . 
     
     
       63. A laminate according to  claim 58 , wherein the silicone compound contains a group reactive with the epoxy resin and/or the curing agent. 
     
     
       64. A laminate according to  claim 63 , wherein the reactive group is hydroxyl group, C 1-5  alkoxy group, epoxy group or carboxyl group. 
     
     
       65. A laminate according to  claim 58 , wherein the metal hydroxide is a metal oxide containing at least one element selected from the group consisting of aluminum, magnesium, zinc, boron, calcium, nickel, cobalt, tin, molybdenum, copper, iron and titanium. 
     
     
       66. A laminate according to  claim 58 , wherein the metal hydroxide is aluminum hydroxide, magnesium hydroxide or zinc borate. 
     
     
       67. A laminate obtained by impregnating a flame-retardant epoxy resin composition comprising an epoxy resin, a curing agent and a metal hydroxide, into a substrate, curing the impregnated composition to obtain a prepreg, laminating a plurality of the prepregs, and hot-pressing them, 
       wherein the curing agent is a phenolic resin (C) containing, in a molecular chain, a structural unit derived from a phenol (A) and a structural unit derived from an aromatic compound (B) other than the phenol (A),  
       wherein a content of the metal hydroxide is 10% by mass to 70% by mass relative to a total amount of the flame-retardant epoxy resin composition.  
     
     
       68. A laminate obtained by impregnating a flame-retardant epoxy resin composition comprising an epoxy resin, a curing agent and a metal hydroxide, into a substrate, curing the impregnated composition to obtain a prepreg, laminating a plurality of the prepregs, and hot-pressing them, 
       wherein the epoxy resin is a novolac epoxy resin (D) obtained by glycidyletherifying a phenolic hydroxyl group of a phenolic resin (C) containing, in a molecular chain, a structural unit derived from a phenol (A) and a structural unit derived from an aromatic compound (B) other than the phenol (A),  
       wherein a content of the metal hydroxide is 10% by mass to 70% by mass relative to a total amount of the flame-retardant epoxy resin composition.  
     
     
       69. A laminate obtained by impregnating a flame-retardant epoxy resin composition comprising an epoxy resin, a curing agent and a metal hydroxide, into a substrate, curing the impregnated composition to obtain a prepreg, laminating a plurality of the prepregs, and hot-pressing them, 
       wherein the curing agent is a phenolic resin (C) containing, in a molecular chain, a structural unit derived from a phenol (A) and a structural unit derived from an aromatic compound (B) other than the phenol (A), and  
       the epoxy resin is a novolac epoxy resin (D) obtained by glycidyletherifying a phenolic hydroxyl group of a phenolic resin (C′) containing, in a molecular chain, a structural unit derived from a phenol (A′) and a structural unit derived from an aromatic compound (B′) other than the phenol (A′),  
       wherein a content of the metal hydroxide is 10% by mass to 70% by mass relative to a total amount of the flame-retardant epoxy resin composition.  
     
     
       70. A laminate obtained by impregnating a flame-retardant epoxy resin composition comprising an epoxy resin, a curing agent and a metal hydroxide, into a substrate, curing the impregnated composition to obtain a prepreg, laminating a plurality of the prepregs, and hot-pressing them, 
       wherein the curing agent is a phenolic resin (C) containing, in a molecular chain, a structural unit derived from a phenol (A) and a structural unit derived from an aromatic compound (B) other than the phenol (A), which satisfies the following conditions (a) to (d):  
       (a) 45≦σ≦100, 3≦E≦12  
        [wherein σ is a bending strength (MPa) of the laminate at 230±10° C. and E is a flexural modulus (GPa) of the laminate at 230±10° C.],  
       (b) 30≦G≦60  
        [wherein G is a proportion (mass %) of the substrate in a total amount of the laminate],  
       (c) F≦45 (mass %), F (mass %)=R×100/X  
        (wherein R is an amount of a thermal decomposition product other than water, generating from a room temperature to 500° C., and X is a content of the resin in the laminate), and  
       (d) 4≦V≦13  
        [wherein V is an amount (V mass %) of a water vapor generating from a room temperature to 500° C., relative to a total amount of the laminate, when the laminate is subjected to thermal decomposition at a temperature elevation rate of 10° C./min at an air flow rate of 0.2 liter/min].  
     
     
       71. A laminate obtained by impregnating a flame-retardant epoxy resin composition comprising an epoxy resin, a curing agent and a metal hydroxide, into a substrate, curing the impregnated composition to obtain a prepreg, laminating a plurality of the prepregs, and hot-pressing them, 
       wherein the epoxy resin is a novolac epoxy resin (D) obtained by glycidyletherifying a phenolic hydroxyl group of a phenolic resin (C) containing, in a molecular chain, a structural unit derived from a phenol (A) and a structural unit derived from an aromatic compound (B) other than the phenol (A), which satisfies the following conditions (a) to (d)  
       (a) 45≦σ100, 3≦E≦12  
        [wherein σ is a bending strength (MPa) of the laminate at 230±10° C. and E is a flexural modulus (GPa) of the laminate at 230±10° C.],  
       (b) 30≦G≦60  
        [wherein G is a proportion (mass %) of the substrate in a total amount of the laminate],  
       (c) F≦45 (mass %), F (mass %)=R×100/X  
        (wherein R is an amount of a thermal decomposition product other than water, generating from a room temperature to 500° C., and X is a content of the resin in the laminate), and  
       (d) 4≦V≦13  
        [wherein V is an amount (V mass %) of a water vapor generating from a room temperature to 500° C., relative to a total amount of the laminate, when the laminate is subjected to thermal decomposition at a temperature elevation rate of 10° C./min at an air flow rate of 0.2 liter/min].  
     
     
       72. A laminate obtained by impregnating a flame-retardant epoxy resin composition comprising an epoxy resin, a curing agent and a metal hydroxide, into a substrate, curing the impregnated composition to obtain a prepreg, laminating a plurality of the prepregs, and hot-pressing them, 
       wherein the curing agent is a phenolic resin (C) containing, in a molecular chain, a structural unit derived from a phenol (A) and a structural unit derived from an aromatic compound (B) other than the phenol (A), and  
       the epoxy resin is a novolac epoxy resin (D) obtained by glycidyletherifying a phenolic hydroxyl group of a phenolic resin (C′) containing, in a molecular chain, a structural unit derived from a phenol (A′) and a structural unit derived from an aromatic compound (B′) other than the phenol (A′), which satisfies the following conditions (a) to (d):  
       (a) 45≦σ≦100, 3≦E≦12  
        [wherein σ is a bending strength (MPa) of the laminate at 230±10° C. and E is a flexural modulus (GPa) of the laminate at 230±10° C.],  
       (b) 30≦G≦60  
        [wherein G is a proportion (mass %) of the substrate in a total amount of the laminate],  
       (c) F≦45 (mass %), F (mass %)=R×100/X  
        (wherein R is an amount of a thermal decomposition product other than water, generating from a room temperature to 500° C., and X is a content of the resin in the laminate), and  
       (d) 4≦V≦13  
        [wherein V is an amount (V mass %) of a water vapor generating from a room temperature to 500° C., relative to a total amount of the laminate, when the laminate is subjected to thermal decomposition at a temperature elevation rate of 10° C./min at an air flow rate of 0.2 liter/min].